Process for producing molybdenum disulfid.



PROCESS FOR PRODUCING MOLYBDENUM DISULFID.

No Drawing.

To all whom it may concern:

Be it known that I, DION L. JOHNSON, a citizen of the United States, residing at Los Angeles, in the countyof Los Angeles, State of California, have invented a new and use ful Process for Producing Molybdenum Disulfid, of which the following is a specification.

' to provide a process by which a disulfid of.

My invention relates to the art of refining metallic salts and more particularly to the art of refining oxidized salts to produce sulfids. More particularly, it refers to a process for recovering molybdenum disulfid from sodium molybdate or from other oxidized molybden salts.

It is a common practice to produce from wulfenite or othermolybdenum ores, an im pure sodium molybdate commercially and hereinafter called somol. Somol chemically consists of Na MoQ with which are usually mixed carbonates, sulfates, phosphates,

arsenates and other sodium compounds. This somol is commonly commercially reduced in the electric furnace, but such re duction processes are troublesome and expensive due to the fact that the sodium-compounds and the sodium content of the somol are corrosive and destructive of furnace linlugs and electrodes.

One of the main objects of my invention is molybdenum may be recovered. from somol by using moderate temperatures. So far as I am aware, there exists no known process by which the disulfid-of molybdenum may be artificially produced, although it is found in an impure state in nature in an ore known as molybdenite. A further object of the process is to pro duce a disulfid of molybdenum which is free from impurities, commonly associated with it in nature and which are deleterious to its further-use, such as phosphorus, arsenic, and

other materials.

It is a further object of my invention to also separate from the final of the impurities, commonly ound in somol. In my rocess the commercial. somol 18 mixed with sulfur, both materials being in their dry state. The'mixture must be ver complete and the materials, must he s ciently broken u so that an intimate mixture may be pro need. I prefer to mm the sulfur with the somol in such a proportion that there will be present in the final inixturo atoms'of'sulfur to 2 inoleculesof UNITED' STATES PATENT OFFICE.

DION 12.. JOHNSON, or'to s ANGELES, canrronnu Specification of Letters Patent.

' in the somol.

roduct certain to utilize veiy 1 Patented Dec. 4, 1917.

Application filed July 7, 1917. Serial No. 179,237.

molybdenum trioxid, the chemical relation of this mixture being 2MoO +7S. In practice, I prefer to use approximately 250 parts by weight of sulfur to 290 parts of molybdenum trioxid. These proportions are of course approximate and may vary considerably without departing from the spirit of my invention.

The intimately mixed mass of material is then subjected to a minimum heat of approximately 500 degrees centigrade. During the heatin of this mass. a chemical reaction takes p ace which may be expressed as follows:

2M0O,,+7S=2Mo S,--3SO The SO produced combineswith the sodium oxid'. base Na,O to produce sodium sulfite Na SO The final mass consists of'the disulfid of molybdenum, the sodium sulfite, and various impurities which were originally The mass after being eated and at the completion of the react-ion, consists of a porous and spongy mass or frit, which breaks up, and disintegrates, when placed in water,"the' sodium sulfite and the impurities of the somol passing into solution in the water. The disulfid of molybdeercised in the selection of the raw material for the furnace so that the proportion of, arsenic and phosphorus in the ferro-mdlybdenum is kept low. In practice in steel making the phosphorus percentage is measured to three decimal places and the proportion is watched very carefully as a high proportion of phosphorus ruins the steel. Due to these facts lar e bodies of molybdenum ore, high in phosp orus and arsenic have hitherto been unavailable for the. reduction of somolwhich it is intended to ator use inthe electric furnace in the production of retromolybdenum. By my process it is possible ure vsomol to produce which -is.free fromyob molybdenum jectionable impurities particularly hosphorus and arsenic, thls molybdenum 'sulfid being readily reduced in the electric furnace to produce a ferro-molybdenum of great urity. My process therefore makes availal fle large bodies of molybdenum ores which are high in hosphorus', arsenic, or other impurities and which are at present unworkable by any commercially known process.

I claim as my invention 1. The process of producing molybdenum sulfidfrom sodium molybdate which comprises finely dividing the molybdate; intimately mixing said molybdate with finely divided sulfur; in the approximate proportion of 290 pounds of molybdenum trioxid content to 250 pounds of sulfur; and sub jectin the mixture to the action of heat.

2. 'l lie process of producing molybdenum sulfid from sodium molybdate which comprises finely dividing the molybdate; intimately mixing said molybdate with finely divided sulfur; in the approximate proportion of 290 pounds of molybdenum trioxid content-to 250 pounds of sulfur;- and subjecting the mixture to'a heat of at least 500 degrees centigrade.

3. The process of separatin molybdenum from somol containing hospiorus, arsenic, or other objectionable e emen'ts which comprises-finely dividing the somol; intimately copies of this patent may-be obtained for five cents ml, by addressing the Washington, D. G.

mixing the somol with free sulfur; subjecting the mixture to the action of heat for the purpose of producing a water insoluble molybdenum disulfid and thereafter removin all soluble matter including objectionable phosphorus" and arsenic compounds from the mixture by leaching.

4=.'The process of claim 6 in which the heating step is carried on at about 500 degrees centig'rade.

The process of claim 6 in which the mixture is in the approximate proportion of 290 pounds of molybdenum trioxid content to 250 pounds of sulfur.

6. The from somol containing hosphorus, arsenic or other objectionable e ements which comprises finely dividing the somol; intimately mixing the somol with free sulfur in the ap proximate proportion of 290 pounds of molybdenum trioxid content to 250 pounds of sulfur; subjecting the mixture to a temperature of about 500 degrees centigrade for the purpose of producin a water insoluble molybdenum disulfid an thereafter removing all phosphorus and arsenic compounds from the mixture by leaching.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 28th day of June, 1917.

DION L. JOHNSON.

process of separating molybdenum commissioner or 1am,

It is hereby certified that in Letters Patent No. 1,248,867, granted Dooernber 4, 1917, upon the application of Dion L. Johnson, of Los Angeles, Caliiomie, for an improvement. in Processes for Producing Molybdenum Disulfid, an error appears in the printed specification requiring correction as follows: Page 2, lines 40 and 43,

plaims 4 and 5, for the numeral "6 read 8; and that the said Lettars Patent.

should be read with this correction therein that tho some may conform to the record 01 the case in the Patent Offica.

Signed and sealed this 26th day of March, A. D., 1918.

mm B. F.. WHITEHEAD,

Acting Commissioner of Patmte; Cl. 23-43. 

